Experimental approaches are proposed to determine if the three major reactions of contemporary translation: amino acid activation, aminoacyl-RNA synthesis, and peptide bond formation, can be facilitated or actively catalyzed by RNA molecules. The method relies on selection of the active molecules from a large pool of arbitrary RNA sequences (selection-amplification). The proposed method of selection, for product formation, is complementary to existing methods for selection of novel catalysts such as affinity for transition state analogues. These experiments potentially define the current biological role of ribozymes, possibly placing RNA catalysis at the heart of translation. In addition, demonstration of one or more of these reactions would help rationalize an ancestral "RNA world" in which synthesis of peptides was carried out by RNA molecules.